Although the physical design of communications and electronics systems has in recent years seen extensive advances in terms of simplification, miniaturization, circuit integration, and the like, the interconnection between system components and mounting frames still relies largely on individual conductors assembled in cables for power distribution and signal transmission. In many systems, terminations from the many circuit units are collected at common points where terminals are provided to which individual cable conductors must be joined. Although the art has offered improvements in terminating arrangements for making the electrical connections between the terminals and individual conductors, the problems of facilitating and speeding the individual joining of conductors and terminals remain. Both solder and solderless connections have been employed in the past, in the latter group appearing the well-known insulation piercing terminals. Electrical connection between such terminals and the cable conductors is achieved by slicing through the conductor insulation by means of bifurcated blades extending from the terminals, which blades at the same time seize the bared conductors to make the connections. This method has the obvious advantages that, not only is the tedious and time-consuming soldering step eliminated, but the necessity of first stripping the conductors is also avoided.
Conventionally, the individual cable conductors are first sorted and arranged on a first insulated member mounting the conductors in a pattern corresponding to the spacings of terminal blades retained in a second insulated block member. The two members are adapted to be fitted one to the other during which the blades function as described to make the electrical connections. A unitary connector assembly is thus realized which may be readily separated to permit wiring changes and repair of the connections should this eventually prove necessary. As mentioned, such insulation piercing connections have long been known in the art. One early such arrangement, for example, is described in the Nov. 19, 1918, U.S. Pat. No. 1,285,361 of J. E. Pettibone. There described is a clip means for retaining, side-by-side, a pair of insulated conductors which clip means is aligned with a pair of bifurcated blades. As the conductors and their retaining clip means are brought into engagement with blades, the insulation is pierced to make simultaneous dual electrical connections.
A more recent insulation piercing connector arrangement is disclosed in the patent of B. C. Ellis, Jr., U.S. Pat. No. 3,611,264, issued Oct. 5, 1971. In the connector arrangement there disclosed a plurality of bifurcated blade terminals make simultaneous electrical connections with corresponding conductors held in alignment between the teeth of an indexing strip. In the afore-cited and other prior art insulation piercing arrangements, single conductors make contact with individual bladed terminals. It frequently becomes necessary, however, to terminate more than one conductor on a corresponding individual bladed terminal. A bladed terminal for making such two-conductor connections is disclosed in the patent of R. P. Reavis, Jr., U.S. Pat. No. 4,040,446, issued Sept. 6, 1977. A terminal is there described which incorporates two bifurcated blades in one structure, the blades lying one above the other. The cutting portions of the blades, however, appear at opposite ends of the bifurcations, that is, the cutting portion of one blade lies at the open end of the bifurcation while that portion of the other blade lies at the base of the bifurcation. A first conductor, as it is manually forced between both blade bifurcations, is seated to the base of the latter blade where its insulation is pierced. A second conductor is then also forced between both blade bifurcations but only so far as the cutting edges of the other blade at its open end. Two conductors are thus sequentially connected to the two-bladed terminal. Although dual connections to a single terminal may in this manner be reliably achieved, the individual insertion of what, in many cases, may be large numbers of conductor pairs in their respective double-blades terminals remains tedious and time-consuming and, therefore, costly. It is to this problem of simplifying and facilitating the insertion of large numbers of conductor pairs in their respective terminals to which the connector assembly of this invention is chiefly directed.